An academic journal is a type of periodical that scholars use to share new research. Each issue of an academic journal contains new content, and may include editorials, opinion pieces, reviews of books or software, articles that review existing literature on a special topic, and articles that describe an original research project undertaken by the author.
Peer Review in academic journals is a process that helps ensure that quality of that research. Peer reviewed articles may also be described as refereed articles or scholarly articles.
The flowchart below illustrates the lifecycle of a peer reviewed article.
Predatory journals are journals that exploit researchers by charging fees to publish research without providing rigorous peer review. This results in journals that claim to be peer-reviewed, but they publish research that may be low in quality. When you are searching for peer-reviewed articles, it's possible that you will come across an article that was published in a predatory journal. This can especially be an issue when you are using a search tool that does not curate content (such as Google Scholar).
Beall's List is a list of journals that may be predatory. This list is not without controversy- there is disagreement about whether some journals should be on this list or not- and it does not list every predatory journal that might be out there. If you find an article and you aren't sure if it is predatory or from a high-quality journal, a librarian or a professor in that field may be able to help you figure it out.
Google Scholar Metrics is a good resource to find a list of the top journals in a particular field.